same problem, diff day

[RagingPanda]

This is starting to get on my nerves now. My 90 240SX(SOHC) with 180k miles keep on messing with me. I have back firing, idles at 1200RPM after warm up, misfiring, and it be losing power for 3 seconds or so everytime i shift gear. I've used Seafoam on my brakebooster line, motor, and fuel tank to clean the injectors, change the spark plugs, plugs wiring, distributor cap and rotor, cleaned my throttle body and MAF. What is the problem? I've searched and see something about the timing. How do you do that? Could my injectors be the cause?If so i can go to a place to get them clean instead of buying new ones($120 each).

[float_6969]

Check for vacuum leaks. Take a can of carb cleaner and start spraying it on all the vacuum lines. If you spray it on one and the throttle speed changes (ususally slows down) you just found your leak.